Gear shifting systems, where shifting occurs by means of axial displacement of sliding sleeves, are known from the state of the art. This way, the sliding sleeve concerned can connect an idler wheel to be shifted form-locking with a main shaft. Displacement of the sliding sleeve is accomplished in the familiar gear shifting systems through shifting elements, such as drivers, shift rails and shift forks. In order to accommodate these necessary components in the transmission, additional operations are required on the gearbox housing, which are disadvantageous.
Among other things, a shifting mechanism in which a threaded spindle is driven by an electric motor is known from the U.S. Pat. No. 4,498,350 publication. An axially displaceable element is provided on the threaded spindle, which is connected via spring elements to a frame, which is likewise axially displaceable by rotating the threaded spindle. An actuating element is, in turn, provided on the frame, which can selectively engage a first or a second gear wheel with the actuating element through the axial displacement of the frame.
This familiar shifting mechanism has a very complicated configuration in terms of its constructional layout. Furthermore, a large number of elements is absolutely required for actuating the one or the other gear wheel.
The present invention is based on the objective of proposing a gear shifting system in accordance with the kind described above, which has the lowest possible number of components and nevertheless enables simple and secure actuation of the gear shifting system.